using System;
using System.ComponentModel.DataAnnotations;
using System.Data.Entity;
//my model
public class Roll
{
[Key]
public uint Id { get; set; }
public long RandomSeed { get; set; }
public string Expression { get; set; }
public DateTime DateCreated { get; set; }
public long Total { get; set; }
}
//my context
public class DiceboxContext : DbContext
{
public DbSet<Roll> Rolls { get; set; }
}
//my controller
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.Entity;
using System.Linq;
using System.Web;
using System.Web.Mvc;
namespace dicebox.Controllers
{
public class RollController : Controller
{
private DiceboxContext db = new DiceboxContext();
//
// GET: /Roll/
public ActionResult Index()
{
return View(db.Rolls.ToList());
}
//
// GET: /Roll/Details/5
public ActionResult Details(int id = 0)
{
Roll roll = db.Rolls.Find(id);
if (roll == null)
{
return HttpNotFound();
}
return View(roll);
}
//
// GET: /Roll/Create
public ActionResult Create()
{
return View();
}
//
// POST: /Roll/Create
[HttpPost]
public ActionResult Create(Roll roll)
{
if (ModelState.IsValid)
{
db.Rolls.Add(roll);
db.SaveChanges();
return RedirectToAction("Index");
}
return View(roll);
}
//
// GET: /Roll/Edit/5
public ActionResult Edit(int id = 0)
{
Roll roll = db.Rolls.Find(id);
if (roll == null)
{
return HttpNotFound();
}
return View(roll);
}
//
// POST: /Roll/Edit/5
[HttpPost]
public ActionResult Edit(Roll roll)
{
if (ModelState.IsValid)
{
db.Entry(roll).State = EntityState.Modified;
db.SaveChanges();
return RedirectToAction("Index");
}
return View(roll);
}
//
// GET: /Roll/Delete/5
public ActionResult Delete(int id = 0)
{
Roll roll = db.Rolls.Find(id);
if (roll == null)
{
return HttpNotFound();
}
return View(roll);
}
//
// POST: /Roll/Delete/5
[HttpPost, ActionName("Delete")]
public ActionResult DeleteConfirmed(int id)
{
Roll roll = db.Rolls.Find(id);
db.Rolls.Remove(roll);
db.SaveChanges();
return RedirectToAction("Index");
}
protected override void Dispose(bool disposing)
{
db.Dispose();
base.Dispose(disposing);
}
}
}
其中大部分是样板自动生成的代码.每当我点击除了获取/滚动/创建操作之外的任何操作时,它都会出现以下错误消息:
System.Data.Entity.Edm.EdmEntityType: : EntityType ‘Roll’ has no key defined. Define the key for this EntityType.
System.Data.Entity.Edm.EdmEntitySet: EntityType: EntitySet ‘Rolls’ is based on type ‘Roll’ that has no keys defined.
但正如您已经看到的那样,有一个关键定义.还有一个为数据库表“Rolls”定义的键支持该模型.我从谷歌得到的每个答案建议添加[Key]注释,我已经有了.
我究竟做错了什么?
最佳答案 将Id更改为int:
public int Id { get; set; }
我将您的代码复制到一个新的MVC项目中,搭建了索引,创建和编辑视图,我能够创建和编辑Rolls,没有任何问题.